Williams and Radwanska are the only top-five seeds remaining in the women's draw. The winner of this possible matchup will be a big favorite to win the final.

Williams has won all five previous meetings with Radwanska, including two wins at Wimbledon. She's only lost one set in those meetings. Unless Radwanska flips a switch she's never flipped before, a win over Williams seems unlikely.

Sabine Lisicki and the winner of the Laura Robson-Kaia Kanepi match still stand in Williams' path en route to the semifinals, but the defending champion is playing great tennis.

None of her possible opponents should give her much issue.

Radwanska has a more difficult task at hand. She should handle Tsvetana Pironkova without issue, but beating the winner of the Li Na-Roberta Vinci match will be more difficult. Still, Radwanska has proven she's at least ready to challenge the elite players in the world.

No. 17 Sloane Stephens vs. No. 8 Petra Kvitova

Stephens may have lucked out with so many potentially tough opponents losing early in the tournament. As it stands, Kvitova is the highest seed remaining in the bottom portion of the bracket.

The two have never played before and neither has been expressly dominant in the tournament so far.

Both Stephens and Kvitova have been extended to three sets in each of their matches. While a Stephens-Williams final would be great for the sport, Kvitova's left-handedness will give the more inexperienced Stephens an issue.

The window is still open for a Grand Slam final between the two Americans, but not this year.

Men's Semifinal Predictions

No. 1 Novak Djokovic vs. No. 4 David Ferrer

Djokovic has two potentially tough matchups ahead of him before he reaches the semifinals. In the round of 16, he will take on Tommy Haas whom he beat in straight sets at the French Open.

Even though that match went over without peril for Djoker, Haas did win the meeting before the Roland Garros clash.

If Djokovic beats Haas, as I predict he will, he'll face the winner of Bernard Tomic and Tomas Berdych. The latter should win and that would set up an interesting quarterfinals battle.

Djokovic has won 13 of their 15 meetings, but Berdych won the most recent encounter in Rome. Because Djokovic rises to the occasion in Grand Slam tournaments, he should beat Berdych.

As for Ferrer, I have an inkling to pick Juan Martin del Potro over him in a potential quarterfinal meeting, but Ferrer has dominated the Argentinian since he seemingly peaked in 2009.

At 24 years old, del Potro could make this his second breakout performance after winning the U.S. Open in 2009, but the safe pick is Ferrer.

Expect Djokovic to manhandle Ferrer the way the elite players genuinely do. Ferrer is the gatekeeper to elite status in men's tennis. He sits just on the outside looking in, but he rejects entry for players like del Potro.

With Roger Federer out of the tournament, Murray has his best opportunity to end England's drought at Wimbledon. None of the men on his side of the draw should be able to keep him from the final—and that includes Janowicz.

The No. 24 seed won't have to contend with anyone with a long list of success at Wimbledon en route to facing Murray. His opponent during the round of 16 is Jurgen Melzer, a 32-year-old who has never been past the fourth round.

Janowicz reached the third round last year and he's an up-and-coming player whose improved play is no shock.

The 6'8" hard-serving 22-year-old has a bright future, but he's not quite ready to make his mark. He's played well up to this point, but if and when he takes on Murray—as I expect will happen in the semifinals—he will be taught a lesson.